I'm not a conservative, but I think I can fairly articulate their views. Actual conservatives can correct me where they see fit.
As many of them are ostensibly concerned with law and order, the Constitution is the bedrock of American law and order. Liberal attacks on the second amendment with gun control laws and on the first amendment, by characterizing hate speech and trying to get social media companies to police it, undermine the representation the Constitution affords every American citizen. Liberals seem willing to undermine the constitutional foundation of the country in order to "push an agenda". That's why Biden is often portrayed as an unlawful government executive that gratuitously overreaches the limits of his office. Similarly, being worried about the strategies and tactics that Trump and other Republican politicians use is fine, but indicting them four times, and throwing people in jail for "inciting violence" is considered much too far for the conservative. Using the law in that way weaponizes it against people earnestly defending their beliefs, and is viewed as a slippery slope into authoritarianism.
Economic policy is another huge area of concern for the conservative. Dedicated to American free enterprise, which is axiomatically the optimal way to produce and distribute resources unless proven otherwise, economic policies that interfere with the invisible hand actively harm the population. So, for example, sure, a wealth tax would redistribute wealth and maybe provide free school lunches for kids. But what is the opportunity cost? More sophisticated conservative economic analysis (like that from AEI, Cato, the Heritage Foundation, or similar) often focus on the potential of lost benefits of leftist economic policy. Wealth redistribution, for the conservative, is like cutting your foot off to run faster due too lost weight. Leftist economic policy undermines the economic security of the nation.
And social policy is a huge concern, too. The whole crisis of masculinity is a example, where they believe young boys and men are taught to hate who they intrinsically are. Conversely, transgender people invert and poison the "natural order". Such social policies undermine the United States in multiple ways, but the biggest is cultivating "weakness". Boys and men who are taught that masculinity is toxic won't be there to enact the necessary violence against aggressors in their personal lives, let alone be there for the nation when the time for war comes. They won't have the ability to overcome challenges, which all men face. Instead, they'll lean into their feelings and sulk in depression because the masculinity required, they'll be taught, can hurt them and those around them. That is, for the conservative, social policy is like caring for others at the expense of the self; it's collectivism. And by not encouraging and cultivating the uniquely American individualistic masculinity that's made us a super power in the few centuries we've been a country, it puts the global American hegemony at risk, which could be catastrophic for the world.
There's more. But those are probably the most salient issues that I can think of off the top of my head.